English
Related papers

Related papers: The braided Ptolemy-Thompson group $T^*$ is asynch…

200 papers

In this paper it is proved that the pure braided Thompson's group BF admits a bi-order, analog to the bi-order of the pure braid groups.

Group Theory · Mathematics 2007-05-23 Jose Burillo , Juan Gonzalez-Meneses

The purpose of this article is prove that Thompson's group F is amenable. The methods developed will then be used to prove a generalization of Hindman's theorem for the free nonassociative binary system on one generator.

Group Theory · Mathematics 2012-10-02 Justin Tatch Moore

Symplectic torus bundles $\xi:T^{2}\to E\to B$ are classified by the second cohomology group of $B$ with local coefficients $H_{1}(T^{2})$. For $B$ a compact, orientable surface, the main theorem of this paper gives a necessary and…

Symplectic Geometry · Mathematics 2007-05-23 Peter J. Kahn

In a previous work [11], the author considered a representation of the braid group \rho: B_n\to GL_m(\Bbb Z[q^{\pm 1},t^{\pm 1}]) (m=n(n-1)/2), and proved it to be faithful for n=4. Bigelow [3] then proved the same representation to be…

Group Theory · Mathematics 2007-05-23 Daan Krammer

S. Bigelow proved that the braid groups are linear. That is, there is a faithful representation of the braid group into the general linear group of some field. Using this, we deduce from previously known results that the mapping class group…

Geometric Topology · Mathematics 2007-05-23 Mustafa Korkmaz

We show that the endomorphisms of a compact connected group that extend to endomorphisms of every compact overgroup are precisely the trivial one and the inner automorphisms; this is an analogue, for compact connected groups, of results due…

Group Theory · Mathematics 2023-09-26 Alexandru Chirvasitu

Dehn twists around simple closed curves in oriented surfaces satisfy the braid relations. This gives rise to a group theoretic from the braid group to the mapping class group. We prove here that this map is trivial in stable homology with…

Algebraic Topology · Mathematics 2007-05-23 Yongjin Song , Ulrike Tillmann

We show that labelled Thompson groups and twisted Brin--Thompson groups are all acyclic. This allows us to prove several new embedding results for groups. First, every group of type $F_n$ embeds quasi-isometrically as a subgroup of an…

Group Theory · Mathematics 2025-10-21 Martin Palmer , Xiaolei Wu

This paper introduces iterated monodromy groups for transcendental functions and discusses them in the simplest setting, for post-singularly finite exponential functions. These groups are self-similar groups in a natural way, based on an…

Dynamical Systems · Mathematics 2020-04-28 Bernhard Reinke

A group is boundedly acyclic if its bounded cohomology with trivial real coefficients vanishes in all positive degrees. Amenable groups are boundedly acyclic, while the first non-amenable examples were the group of compactly supported…

Group Theory · Mathematics 2022-06-14 Francesco Fournier-Facio , Clara Loeh , Marco Moraschini

Group cohomology of polynomial growth is defined for any finitely generated discrete group, using cochains that have polynomial growth with respect to the word length function. We give a geometric condition that guarantees that it agrees…

K-Theory and Homology · Mathematics 2018-08-08 Ralf Meyer

We study generic properties of topological groups in the sense of Baire category. First we investigate countably infinite (discrete) groups. We extend a classical result of B. H. Neumann, H. Simmons and A. Macintyre on algebraically closed…

We show that any twisted Dijkgraaf-Witten representation of a mapping class group of an orientable, compact surface with boundary has finite image. This generalizes work of Etingof, Rowell and Witherspoon showing that the braid group images…

Quantum Algebra · Mathematics 2017-11-15 Paul Gustafson

We give sufficient conditions for left- and bi-orderability of fundamental groups of Ore categories in terms of indirect factors, including Thompson groups and many of their generalizations. Besides recovering known results, we prove that…

Group Theory · Mathematics 2025-03-17 Davide Perego , Matteo Tarocchi

We describe pure braided versions of Thompson's group F. These groups, $BF$ and $\hat{BF}$, are subgroups of the braided versions of Thompson's group V, introduced by Brin and Dehornoy. Unlike V, elements of F are order-preserving self-maps…

Group Theory · Mathematics 2018-03-19 Thomas Brady , Jose Burillo , Sean Cleary , Melanie Stein

Let $\Lambda$ be a row-finite and source-free higher rank graph with finitely many vertices. In this paper, we define the Higman-Thompson like group $\Lht$ of the graph C*-algebra $\mathcal{O}_\Lambda$ to be a special subgroup of the…

Operator Algebras · Mathematics 2021-05-19 Dilian Yang

We prove that Thompson's group $V$ is acyclic, answering a 1992 question of Brown in the positive. More generally, we identify the homology of the Higman-Thompson groups $V_{n,r}$ with the homology of the zeroth component of the infinite…

Group Theory · Mathematics 2019-05-24 Markus Szymik , Nathalie Wahl

We investigate a group $B\_\bullet$ that includes Artin's braid group $B\_\infty$ and Thompson's group $F$. The elements of $B\_\bullet$ are represented by braids diagrams in which the distances between the strands are not uniform and,…

Group Theory · Mathematics 2007-05-23 Patrick Dehornoy

It is proved that any countable index, universally measurable subgroup of a Polish group is open. By consequence, any universally measurable homomorphism from a Polish group into the infinite symmetric group $S_\infty$ is continuous. It is…

Logic · Mathematics 2011-04-19 Christian Rosendal

In any category with a reasonable notion of cover, each object has a group of scissors automorphisms. We prove that under mild conditions, the homology of this group is independent of the object, and can be expressed in terms of the…

K-Theory and Homology · Mathematics 2024-08-27 Alexander Kupers , Ezekiel Lemann , Cary Malkiewich , Jeremy Miller , Robin J. Sroka